It was nearly a year ago when we got our first look at the new BMW 4 Series Convertible, so it was surely only a matter of time before its coupe counterpart would begin testing. At long last, a next-generation BMW 4 Series Coupe prototype has been spotted being carried on a transport truck. The prototype is heavily camouflaged, but the production headlights suggest development is slightly ahead of the convertible.

BMW has previously said the new 4 Series will look a lot different to the 3 Series, which is evident from the prototype's slimmer headlights and lower roofline, resulting in a sporty profile. The regular 4 Series Coupe will also pave the way for a new high-performance M4, which was also recently spied in convertible guise.

We don't get a look inside the coupe's cabin, but previous spy shots of the 4 Series convertible have confirmed the interior will be updated with a new dashboard akin to the new 3 Series and Z4, featuring an updated iDrive system, a new shifter, digital gauges, and new switchgear.

Thanks to BMW's CLAR modular architecture, the new 4 Series is said to be 100 pounds lighter than its predecessor, which should make it even more enjoyable to drive. As for engine options, the new 4 Series is expected to share the same powertrains as its 3 Series sibling, including a 255-horsepower four-cylinder and 382-horsepower inline-six.

The range-topping M4, on the other hand, will get the same 3.0-liter twin-turbo unit as the new M3, which is expected to produce 473 horsepower and 442 lb-ft of torque in the base model while the range-topping Competition model will reportedly pack 503 hp.

The new BMW 4 Series coupe will most likely be revealed before the convertible by end of this year before both models go on sale in 2020.